Method of production of sound records



Jan, 13, l

V. H. EMERSON METHOD OF PRODUCTION OF SOUND RECORDS F'iledv April 20, 1920 flftlll) Patented Jan. 13', 1925.

STATES;

VICTOR H. EMERSON, or'NEw YORK, NJ Y., AssIeNoR "ro EMERSON PHONOGRArn N N 1,522,943 PATENT-OFFICE- Y:corneafiar,, .1Nc. or NRwYoRx, N. Y., A CORPORATION or Naw YORK.

y(inaction or PRODUCTION OR SOUND RECORDS.

" l"Application meanpru 2c, 1920. seriaiNo.` 375,244.

To all 'whom "mayfcnoerm Beit knownthat 1,"VIo'roR H. EMERSON, a citizen ofthe United States, residing at thel city, Vcounftyfand State ofNew York, 5 have inventednew'fanduseful Im rovements in Methodsbf `Production of ound Records, ofwhichV the following is a specification; 1 -Y My invention relates 'to phonograph records andfnfiethods"ofproduction, and more articularly to disk records made up of ayers ofrdfl:`erentlmaterials suitable for respective fu'nctions andhasfor' an object to produce v'a record possessing a maximum of efficiency' an'ddurability at a minimum costoflabor and material.

More specifically described, my improved process contemplates the formation of a record hearing` a layer-of paper or other i fibrousmaterial treated bya "method that not only "improves `its inherent properties adaptable toi record construction, but `is conducive to"amoreperfect'union'with` record solid material -it carries with it, the solid materialupon the surfaces thereof.

To'the attainment of 'this end in'following a preferred form of myv improvedfmethod the following "several" distinctive Vsteps are to betak'en: V y First,-`Lform aldisk'of pa er board or othersuitablefmaterial of the esired` diameterof the record to b e made therefrom, andv provide Ythe 'disk thus formed with the usual centralori'fice for. useboth inconnection with phonograph :machines -when it has been produced, and'also in -facilitating theV making of the record having vreferenceparticwlarly tothe pressing operation. Thispaper shouldbe'suiciently'porous for the absorption of material in solution and for this pur- 4 pose I. have found blotting paper of the form in generalI commercial use most convenient and adaptable lA liquid cement is then made ofja solutionofA magnesium oxidefi'n powdered form in 'magnesium chloride inthe proportion" of about 100 grams ofmagnesia dissolved in65 cubic centimeters of the chloride, which solution I'shallhereinafter refer to as magnesium cement; andthen the disk of blotting-paperis impregnated with the solution either by immersing into the cement until the pores, that is, the interstices between the bres of the paper board, become sufficiently filled and saturated with the cement, or by introducing thecementin the form of a f paste which may be` spread upon both surfaces of the paper accom lishing practically the same result as by p acing in the bath. Thus the paper disk becomes completely transformed,especially at and immediately belowits surface areas, into av clayey or stone-likebody, .having taken on the -properties of hardness, toughness and general firmness `necessary to a perfect pressed record. u

'After .the paper has been thus saturated with the magnesium cement, it will be found upon examination that the earthy consistency is more inevidence at the surface than within the body portion of the disk member, and therefore .the dee er the paper is penetrated the less will e the amount of the magnesia found vtohave been incorporated therein. This vis due to the very simple and obvious tendency of natural laws. As the liquid chloride of magnesium is drawn by capillary attraction between the fibres ofthe material, the farther it travels theless of the portions being lost in theprocess of infiltration that-ensues. Y

l The inability of the blotting `paper to carry the solid materials uniformly into its interior'is beneficial rather 'than injurious for the reason that the paper in its natural form is somewhat yielding, and to that extent presents amore wieldy body `portion to, the action of the stamping matrix plates. It should be understood, however, that the yielding property Areferred 4to as conducive to `better stamping results does not interfere with the correctness and .permanence of the record groove Vstamped upon the surface. The property of thepaper is such as to take and hold impressions that have been impressed intots surface. But while Iwish to point out, on the other hand, that this retaining quality or characteristic of the paper is enhanced by the addition of the cement to its fibrous formation, the cushioning feature ofthe less thoroughly saturated middle portions of the paper does not prevent theremaining portions of the pa er from func; tio'nininthe manner-pointe out.

Whlle the foregoing step relative to the application of the cement to the paper body portion has been described in its essential aspects, it will be found serviceable in actice.

throughout with 4 liquid a ent.

water or other suitable The disk having thus been prepared with the cement solution, it isdried outI thoroughly,V and thereupon, after sufiiciently ydrying and hardening the disk thus prepared, one

or both of its stone-like surfaces are covered,

with record material which may be applied in any of the well-known methods, but preferably in the form of a centrally applied thermo-plastic ball-which as the matrix plate, heated to the required degree, is

pressedV into its surface is 4spread cen,

wardly expanding masses will counterbal` ance the clayey or stone-like layer whichis thus held between them'as they expand.'

The record material employed @in this manner is preferably composed of shellac and other ingredients and as `the shellac comes in contactwvith the lithicsurfaceof the magnesium cement with which the disk has previousl been treated in the manner described, a

In the accompanying drawings illustrative of apparatus employed in the practice of my rocess, and a form ofthe product there-v of, igure l is an edge Viewvof a recordfin a 'press in process of being formed, and

Fig. 2 is an edge view7 ofthe record after `havingbeen pressed into final shape.

Referring to the drawings The numeral 1` represents a disk formed preferably from a` sheet of blotting paper of tbe desired thickness which has been died out to the required diameter with the usual central ori The disk Yl is referably firstdampened with water and tien treated with a cement composed of 100 grams of magnesia made:

into a paste by being dissolved in approxi.- mately grams of magnesium chloride, with which amounts I am able to treat three disk surfaces, each of ten inches diameter,

but by increasing the solution `in substantlally the proportion indicated any desired h quantity may be adequately. treated. The

cement 1s most conveniently applied by spreading it over the surfaces which arerdel rm and intimate union takes place which permanently fixes the record material to the surface of the disk."

signed subsequently toreceive, theA coating ofrecord material. Iv" then thoroughly dry,r I

and with a thermoplastic record material preferably in the form of a mass or. ball 2 f i centrally applied to the surface of the"disk,

the disk is placedin--a press" for" stamping records andthe massafterbeing spread over the surface is then impressed permanently` i thereon. -WVhen it is desired to forma double faced record two Vmasses 2 of record material are applied uas` shown .in Fig. 1"

where `they are seen in processofbeing impressed -upon the respective surfaces ofthe disk, while the usual degree` ofM- l'iea-t` isbeing applied-,in any convenient ,wa'y.

`In Fig. 2 is illustratedtlff duced by my process,'havin`g.layer21ofrec ord material shown in exaggerated thickness; j

upon both itssurfaces, into Whichthe matrices .3 forming theupperand Ilower plates.`

respectively of the stamper presshave'imf" pressed asound record'grociva:.f1V

The record inaterialm y'be.applied;"insa-nyT convenient manner butowingfto.A the' com;

paratively firm. natureioffthe body V portion or layer of the record-tobbe(formed, I find it most advantageous. and therefore"V have e given as the preferred method ".ofmyi improved process to usetherecord material in.

the mass. kforms`2 4of thermo-plasticfmaterial applied and-impressed uponlt he surface as` shown-in Fig. lA in process of, formation.

Having described .my inventionfwhat a claim is: V l. 1 i, 1. A method,forl-makingsound records' which` consists inv `d ieing out a disknfrom blotting paper of Ysuitable thickness, immersing the d1sk in a solution of magnesiafqn Athe chloride ofy magnesiumin the,proportionr of substantially.- grammes'iof thek former to` 65 cubiccentimeters ofi-the latter,.-applyinga:

thermo-plastic record;l to the vsurfaces of ,the

disk so treated with magnesiaLa-nd,.impressi ing upon the surfacethereofla sound-record. 2. A method for makingfsou-'ndrecords which consists in preparingvavfdiskof bloteting paper, immersing .the disk in a solution'` of the proportion of-l00` grannnesof magne;

sia i to 65cubic :centimeters "of `.magnesiumV A chloride, applying ya mass ofthermo-plastic record material centrally to theopposite faces of the disk so treated withmag-nesia p and pressing `said. Vmasses between Vsound matrices with the .application offbeat until said re'cordv material covers thefacesbf the'` disk to asubstantially uniform-andrequal.

depth.

- In testimonywhereofl havelihereunto my hand.

- iffo'froril' EMERSON.' `ff 

